Bacterial biofllms are highly complex structures containing a diversity of microenvironments and physiological states. Due to the complex nature in which bacteria grow within a biofllm, the study of these communities requires sophisficated instrumentation that allows for the simultaneous analysis of individual cells within a population. Fortunately, there has recentiy been an explosion of techniques made available, previously used to study eukaryotic organisms, to help us understand the complexities of biofilm development. The primary function of this Core will be to provide the sophisticated instrumentation needed to visualize the specific transcriptional and physiological changes that occur during biofllm development. It will also give important tools and expertise needed for studying biofllm-related infections. Three speciflc aims are proposed to support this function. Specific Aim 1 will be to upgrade and maintain the instrumentation needed to provide biofilm images. This will be achieved by providing an upgrade for an exisfing Zeiss LSM510 META confocal microscope available to our group for use in the study of biofllm structure and development, as well as host tissues infected with S. aureus. As this technology will be an integral component of all four Projects, making available expertise in the use of this instrumentation is also a key part of this aim. Specific Aim 2 will be to provide the technology needed to visualize and isolate specific biofilm substructures and various immune cell populations from biofilms grown in vivo. This newly developed technology for the study of bacterial biofllm will be vital to Projects 1 and 2 for the study of physiological heterogeneity in biofllms. In addition, Project 4 will use this to examine local immunological responses to biofllm-related infections. Finally, Specific Aim 3 will be to provide the technology needed to visualize the progression of infection. This aim will make available an In Vivo Imaging System (IVIS) for use in following the progression of staphylococcal infection, both from the bacterial and host perspective. This technology will allow Project 3 to test the ability of the bacteria to spread to sights throughout the host, and Project 4 to examine the status of specific immune cells in response to biofllm-related infections. Overall, this Core will give our group a state-of-the-art facility that will greatiy enhance our ability to accomplish the objectives of this PPG. RELEVANCE (See instructions):